1. Field of the Invention
This invention relates to condition monitoring systems wherein a plurality of contacts at remote locations or points are monitored at a central location to sense an alarm or status condition at the remote locations.
2. Description of the Prior Art
Examples of prior art condition monitoring systems are described in U.S. Pat. Nos. 3,447,145; 3,451,058; 3,518,653; 3,611,363; 3,644,891; 3,644,894 and 3,714,646. The prior art condition monitoring systems cannot be easily adapted to a wide variety of different applications, each system may have to be modified extensively in order to fit a particular application. Another disadvantage of the prior art systems is that alarms and other indicators associated with the systems can be de-activated by unauthorized persons, thus an alarm condition could be undetected by an authorized person returning after a temporary absense.